Two-Dimensional CH₃NH₃PbI₃ Perovskite Nanosheets for Ultrafast Pulsed Fiber Lasers

Abstract

Even though the nonlinear optical effects of solution processed organic-inorganic perovskite films have been studied, the nonlinear optical properties in two-dimensional (2D) perovskites, especially their applications for ultrafast photonics, are largely unexplored. In comparison to bulk perovskite films, 2D perovskite nanosheets with small thicknesses of a few unit cells are more suitable for investigating the intrinsic nonlinear optical properties because bulk recombination of photocarriers and the nonlinear scattering are relatively small. In this research, we systematically investigated the nonlinear optical properties of 2D perovskite nanosheets derived from a combined solution process and vapor phase conversion method. It was found that 2D perovskite nanosheets have stronger saturable absorption properties with large modulation depth and very low saturation intensity compared with those of bulk perovskite films. Using an all dry transfer method, we constructed a new type of saturable absorber device based on single piece 2D perovskite nanosheet. Stable soliton state mode-locking was achieved, and ultrafast picosecond pulses were generated at 1064 nm. This work is likely to pave the way for ultrafast photonic and optoelectronic applications based on 2D perovskites.

Photonics and Optoelectronics of 2D Metal‐Halide Perovskites

“…Compared to its bulk counterparts and thin NCs films, 2D metal‐halide perovskites are more suitable for investigating intrinsic nonlinear optical properties for its relatively small photocarriers recombination and nonlinear scattering . The nonlinear absorption coefficient of 2D perovskite nanosheet is two orders of magnitude larger than that of the bulk perovskite, and 2D perovskite is able to achieve mode locking at lower power threshold than bulk one, as shown in Figure d.…”

“…and comparable to few‐layers graphene . By transferring suitable 2D perovskite nanosheets onto the end facet of an optical fibre ferrule to fabricate a saturable absorber, a ultrafast picosecond pulses can be generated, as shown in Figure e. However, the nonlinear property such as second harmonic generation (SHG) has been rarely reported in emerging perovskite with form AMX 3 .…”

Optoelectronic Perovskite Synapses for Neuromorphic Computing

“…Today, all‐inorganic perovskite materials are widely used in photovoltaic devices, such as solar cells, photodetectors, and light‐emitting diodes. All‐inorganic perovskite materials with different morphologies have their own advantages in application, and nanoplates have excellent light absorption coefficients, good electrical transmission capacities, and high environmental stabilities; thus, these materials hold potential for preparing optoelectronic synapses in the future.…”

2D Perovskite Sr2Nb3O10 for High‐Performance UV Photodetectors

“…Among them, 2D perovskites have attracted increasing research interest and been applied to diverse fields, such as light‐emitting diodes (LEDs), solar cells, and PDs, because of the advantages peculiar to them . First, inherited from their bulk counterparts and originated from their reduced dimension, 2D perovskites exhibit a variety of intriguing properties, including tunable bandgap, high photoconductive gain, high photoluminescence (PL) efficiency, and nonlinear optical properties . Second, it is found that many properties of 2D perovskites are strongly dependent on their thickness, and the properties show increased sensitivity to applied external fields owing to their ultrathin thickness .…”